Systems and techniques for collecting and analyzing breath samples to detect one or more target analytes are disclosed.

A sulfur chemiluminescence detector includes a heating furnace 210 that includes a gas passage 211 which is a passage extending to left and right, in which an end portion on an outlet side of a column 140 of a gas chromatogram is inserted into an end portion on an inlet side, and a heating means 215 for heating the gas passage, a reaction cell 231 configured to cause gas that has passed through the gas passage to react with ozone, a photodetector 233 configured to detect light emitted from the reaction cell, a housing 240 that houses the heating furnace, the reaction cell, and the photodetector, and an interface 250 that is attached to penetrate a wall of the housing and provided with a column passage 251 through which the column 140 is inserted and a heating means 252 for heating the column passage 251. In the sulfur chemiluminescence detector, the housing is configured to be able to hold the heating furnace in either a state in which the end portion on the inlet side of the gas passage is directed to right or a state in which the end portion on the inlet side is directed to left, and is configured to allow the interface to be attached to either a right wall 242 or a left wall 243. In this manner, the sulfur chemiluminescence detector can be applied to GC systems having various configurations.

In a chemiluminescence type nitrogen oxide concentration meter, a mixed gas of air with its moisture adsorbed by an adsorption apparatus and air that through a fifth flow path without the adsorption apparatus in between is flown into an ozone generator. Therefore, ozone can be generated using air of proper humidity in the ozone generator 7. As a result, ozone can be efficiently generated while suppressing occurrence of metal contamination in the ozone generator 7. Then, in the reaction unit 8, nitrogen oxides in the sample gas are made to appropriately show chemiluminescence using the ozone, and in the detector 9, the intensity of light generated in the reaction unit 8 is detected. Furthermore, in the control unit 10, the concentration of nitrogen oxides in the sample gas is measured, based on the intensity of light detected by the detector 9.

Systems and techniques for collecting and analyzing breath samples to detect one or more target analytes are disclosed.

An inner diameter of an opening of the flow path is larger than a particle diameter of an adsorbent. Therefore, in a state where the flow path 33 is disposed in the container 31, the adsorbent 40 enters the flow path 33 via the opening 33B of the flow path 33. That is, in the adsorption apparatus, the adsorbent is disposed in a region between a side surface portion of the container and the flow path and inside the flow path. Further, in the adsorption apparatus 3, the air flows the region between the container 31 and the flow path 33 and in the flow path 33. Therefore, when the air is flown into the adsorption apparatus 3, the air can be sufficiently brought into contact with the adsorbent 40, and moisture contained in the air can be sufficiently adsorbed.

An exhaust gas analysis device analyzes exhaust gas generated when fuel is combusted. This exhaust gas analysis device includes a first analyzer that measures a concentration of a component to be measured in the exhaust gas, a second analyzer that measures a concentration of CO.sub.2 in the exhaust gas, a storage portion that stores a hydrogen/carbon ratio, which is a ratio between hydrogen and carbon composing the fuel, or an input receiving portion that receives an input of the hydrogen/carbon ratio, a moisture concentration estimating portion that, based on the measured CO.sub.2 concentration and on the hydrogen/carbon ratio of the fuel, estimates a concentration of moisture in the exhaust gas, and a correcting portion that, based on the estimated moisture concentration, corrects the measured concentration of the component to be measured.

The invention is directed to a furnace suited for oxidation of a gaseous starting mixture comprising one or more sulphur compounds to obtain an oxidized gas mixture and reduction of the oxidized gas mixture to obtain a gaseous mixture of reduced sulphur compounds comprising an interior furnace space, an inlet conduit for the gaseous starting mixture, an inlet for supply of an oxygen comprising gas, a ceramic comprising outlet conduit provided with an inlet opening for the mixture of reduced sulphur compounds, an inlet for hydrogen and heating means, wherein the inlet opening of the outlet conduit is comprised of more than one opening which openings fluidly connect the interior furnace space and the interior of the outlet conduit.

Use of a method of identifying the sources of particulates in the atmosphere, including the steps of; quantifying the amount of polycyclic aromatic hydrocarbons and that of nitropolycyclic aromatic hydrocarbons contained in particulates in the atmosphere; and identifying the ratio of combustion-derived particulates in the atmosphere using logical equations derived in advance, which use the amount of polycyclic aromatic hydrocarbons and that of nitropolycyclic aromatic hydrocarbons contained in pre-quantified particulates derived from different combustion sources, and the amount of polycyclic aromatic hydrocarbons and that of nitropolycyclic aromatic hydrocarbons contained in the particulates in the atmosphere obtained in the step of quantifying, allows identification of the sources of particulates in the atmosphere in which mixed particulates from different sources are suspended.

The invention is directed to a method for chemiluminescent sulphur detection wherein the method comprises the following steps. (a) oxidation of a gaseous starting mixture comprising one or more sulphur compounds to obtain an oxidized gas mixture. (b) reduction of the oxidized gas mixture as obtained in step (a) to obtain a gaseous mixture of reduced sulphur compounds in the presence of a ceramic surface. (c) reacting the mixture of reduced sulphur compounds obtained in step (b) with ozone to obtain a sulphur compound in excited state and measuring a chemiluminescent emission of the sulphur compound in excited state to obtain a measure for the amount of sulphur compounds in the gaseous starting mixture. The ceramic surface in step (b) is a magnesium aluminium silicate comprising surface.

A cavity ring down measurement system comprising a light source in optical communication with a detector through an optical cavity wherein the detector is in electronic communication through a gating circuit with a first integrating circuit and a second integrating circuit, controlled to obtain a ring up signal simultaneous with a ring down signal of a plurality of ON-OFF cycles over a single period of time. A process to utilize the system is also disclosed.